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also secret, being usually accompanied at the time by an injunction not to make known the name of the donor, we shall not here seek farther to disclose; preferring to dwell on the comfortable truth, that “there be some persons that will “not receive a reward for that for which God accounts Him“self a debtor: persons that dare trust God with their charity, “ and without a witness."*

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Izaak Walton, Life of Dr. John Donne,' p. 54, ed. Oxford, 1824.

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CHAPTER XXV.

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STEAM-NAVIGATION ITS ORIGIN AND PROGRESS PADDLE-WHEELS

EARLY STEAM-BOATS - PAPIN, HULLS, MILLER, SYMINGTON, FULTON, HENRY BELL, ETC. — MR. JAMES WATT, JUNIOR -HIS VOYAGE IN THE

CALEDONIA," IN 1817, TO GERMANY, BELGIUM, AND HOLLAND H.M.S. THE JAMES WATT THE GREAT EASTERN - NAVAL REVIEW IN 1856 - LOCOMOTIVE STEAM-CARRIAGES — -MR, WATT'S PATENT, AND MR. MURDOCK'S MODEL, OF 1784 — MR. WATT'S VIEWS OF LOCOMOTION ON LAND BY STEAM EDGEWORTH'S SUGGESTION OF A RAILROAD LATIN EPIGRAM.

A SUBJECT which naturally excited a deep, and, indeed, at one time, rather an anxious interest in the breast of the great engineer, when resting in his latter days from the severer labours of his life, was that of steam-navigation. With every confidence in the probable success of such a system, he seems never in any very especial manner to have directed the force of his own mind to the details requisite for carrying it out; a circumstance which is quite explained by the constant demands on his time and attention made by other branches of the steam-engine business, so long as he continued to be actively engaged in its prosecution. He is also said to have observed that “wind was cheaper than steam." But, in times widely different from those in which he had asked his memorable question as to whether “a spiral oar” or “two wheels" were to be preferred for navigation by steam, he lived to know of the first complete and practically useful steam-boat being successfully employed in America; as well as of the British Channel being crossed, and the Rhine navigated by another, under the personal direction of his own son; both vessels,-the American and the British, having been impelled by engines manufactured at Soho, constructed on the principles invented by himself, and not without the benefit of his own inspection and counsels.

We have no intention of here entering at any considerable length on the history of steam-navigation,-a subject which has already been treated of by various competent authorities, and which perhaps offers materials for a still more comprehensive work than any that have yet appeared. But it may generally be remarked, that the introduction of that most valuable mode of conveyance and transport has been quite dependent upon, and nearly co-ordinate with, Mr. Watts improvements on the steam-engine; that before those improvements were made known to the world, nothing of any importance in that way had been accomplished, and little even attempted or imagined ; and that since the full development of those improvements, that perfection of power and safety with which the ocean is now traversed in every direction and to any distance, by vessels impelled by steam, has been rapidly and triumphantly attained.

To this end the ingenious industry of many successive engineers and mechanics has, it is true, eventually conduced: but the master-key which unlocked the power required for the performance of such a task, was the condensation of steam in a vessel separate from the cylinder, together with the means of converting the rectilineal motion of the piston-rod into a rotative one for paddle-wheels, or, as now practised, for a screwpropeller, or “spiral oar.”

We have already sufficiently exposed the fictitious letter in which Solomon De Caus is made to talk, in 1641, to an imaginary Marquis, of “ navigating ships," as well as of moving carriages, and of working other miracles by means of steam.* But the mere use of paddle-wheels, “remi rotatiles," or "rames “ tournantes," moved by animal force, for the progression of boats, appears to have been of considerable antiquity. Not to carry our inquiries further back, they have been fully described by Valturius, in his great work on the Science of War,' in 1472; by William Bourne, in 1578; by Denis Papin, (as having been seen by him in use in England, probably in 1682), in 1690; by Savery, in 1698; by Du Quet, in 1702 and 1735;

* See p. 125, supra.

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by the Comte de Saxe, in 1732, &c. Papin, also, in 1690, unquestionably suggested the employment of the atmosphere as a power, with a vacuum formed by the condensation of steam beneath a piston in a cylinder, the power being communicated by toothed and paddle-wheels “ad naves adverso “ vento provehendas,”* “ to propel ships against the wind :" and he represented the greatest probable obstacle to the construction of such a machine to be the difficulty of getting cylinders, of adequate size, sufficiently well made for the purpose they were intended to serve.

Of the mere ingenuity of his suggestion, so far as it went, there cannot, of course, be a doubt; but this, like some others of his mechanical ideas, he seems not to have seriously attempted to reduce to practice, and, if he had done so, he would have found how entirely insufficient was the apparatus he proposed, now dignified by some writers with the name of his steamengine, to produce such effects as he desired. The mechanical difficulty, also, which he has specified, although unquestionably very considerable, was only one of many, not less formidable, which Mr. Watt's more comprehensive view foresaw; and which it needed all the most constant and anxious exertions of his more powerful practical genius to encounter and overcome. Since the days of Papin, indeed, the experience of a century and a half has fully enabled us to judge how great was the distance between the imperfect conception of a project, such as he suggested in the passage quoted above, and its successful consummation.

It still, curiously enough, remains uncertain whether Jonathan Hulls carried into effect the more elaborate invention for which he obtained a patent in 1736, and which he set forth in his celebrated pamphlet entitled “A Description and Draught of a new-invented Machine for carrying Vessels or

a Ships out of or into any Harbour, Port, or River, against · Wind and Tide, or in a Calm :' London, 1737. But he has, at least, minutely described the introduction of a Newcomen's engine into a large boat or barge to be employed as a tug,

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* See pp. 140, 141, suprà.

and has delineated such a vessel, fitted with fan (or paddle) wheels, towing a ship of war of upwards of thirty guns. His work, which seems to have been long overlooked, is now not common, and it is still more rare to meet with a copy containing the curious and highly illustrative engraving which forms its frontispiece; but it affords the strongest evidence which we possess, of a marine atmospheric steam-engine, working by paddle-wheels, having been constructed,—or, at all events, fully devised and figured in action,-60 early as the period in question.

After the date of Mr. Watt's patent of 1769, (the great pivot on which all real advancement in the steam-machinery of modern times has turned), it is said that, in the United States, Mr. Ellicot, in 1775, and T. Paine, (less favourably known by his writings), in 1778, suggested the use of steam for propelling boats ; as the Abbé Arnal did in France in 1781, for inland navigation; while in 1782 the Marquis Jouffroy built a steam-boat, which was tried on the Saône, but did not succeed. In 1783, Mr. James Rumsey of Virginia and Mr. John Fitch of Philadelphia both proposed methods of propelling boats, the one by a current of water forced out at the stern, and the other by paddles, but not in the form of wheels. It is said that Mr. Fitch constructed a steam-boat which was navigated between Bordentown and Philadelphia, but was soon laid aside.

In 1787, Mr. Miller of Dalswinton published a description, with engravings, of a triple vessel, propelled by paddle-wheels, turned by means of cranks, intended to be worked by men; adding, “I have also reason to believe that the power of the steam-engine may be applied to work the wheels, so as to

give them a quicker motion, and, consequently, to increase " that of the ship.” In 1788, Mr. Miller employed Mr. William Symington, of Wanlockhead, in Dumfries-shire, along with Mr. James Taylor, to superintend the construction of a small steam-engine in a pleasure-boat on Dalswinton Loch. This succeeding well, induced him to employ Mr. Symington to construct a larger steam-engine at Carron, for one of Mr. Miller's boats on the Forth and Clyde Canal, which was tried

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